The AC "sweet spot" recommended by @rainforestplumbingandac is to set your thermostat 4 to 5 degrees higher than normal during a vacation, and avoid turning off the AC completely. This helps maintain a balance between comfort and energy savings while preventing potential issues caused by high humidity levels in the home.
Heat pumps reduce electricity usage by transferring heat between the indoors and outdoors instead of generating heat like traditional furnaces or electric heaters. They absorb heat from the outside air or ground and concentrate it to warm a building. This process is more efficient, using only one unit of electricity to move three to six units of heat, resulting in lower energy consumption and costs.
Setting a higher thermostat on vacation saves money because it reduces the workload on your air conditioning system, leading to lower energy consumption. The closer the indoor temperature is to the outdoor temperature, the less the air conditioner has to run. This prevents the AC from working hard to cool down the house when you return, which can be costly. A higher thermostat setting also prevents increased humidity that could affect your home's interior and belongings.